In an existing macro cellular network, because a cell radius is generally large, coverage is hardly available to a user located in an area on an edge, and performance cannot be ensured. Moreover, in a hotspot traffic area of a macro cell, a situation in which experience of some users cannot be ensured also exists because there is a large quantity of users. However, emergence of a heterogeneous network (Hetnet for short; also referred to as a macro-micro network) solves a problem that performance of a user cannot be ensured in the macro cellular network. In a heterogeneous network topology, a micro cell may be used to fill a coverage hole of a macro cell, or a micro cell may be used to absorb traffic in a hotspot traffic area of the macro cell. In this way, a cell capacity can be improved so as to ensure user experience.
In the heterogeneous network, transmit power of a micro cell base station is lower than transmit power of a macro cell base station (transmit power of a macro base station is generally 43 dBm, and transmit power of a micro base station is generally 37 dBm or 30 dBm). Therefore, a balancing point of uplink power is different from that of downlink power, that is, a point at which downlink power from a macro base station to a user equipment (UE for short) is the same as downlink power from a micro base station to the user equipment is different from a point at which uplink power from the UE to the macro base station is the same as uplink power from the UE to the micro base station. Therefore, a soft handover area may also exist. In the soft handover area, power of the UE is controlled by both the micro base station and the macro base station, and a criterion for power control is as follows.
The UE makes a response by performing a power decreasing operation as long as a cell in an active set sends a “power decreasing” instruction. The UE makes a response by performing a power increasing operation only when all cells send a “power increasing” instruction to the UE. However, in the heterogeneous network, when the UE is located in a soft handover area in which a macro cell serves as a serving cell and a micro cell serves as a non-serving cell, High Speed Downlink Packet Access (HSDPA for short) data is sent by the macro base station, and an information feedback of a high speed dedicated physical control channel (HS-DPCCH for short) is sent to the macro base station; however, still in this soft handover area, uplink power from the UE to the micro base station is higher than that from the UE to the macro base station, and therefore, the UE is subject to “power decreasing” control of the micro base station. As a result, power of HS-DPCCH received by the macro base station is extremely low, which directly affects HS-DPCCH demodulation performance.
To improve the HS-DPCCH demodulation performance, in the prior art, a power offset of the HS-DPCCH is generally raised. However, the power offset of the HS-DPCCH is limited, and in some cases, even though a largest power offset is configured for the HS-DPCCH, a requirement of the HS-DPCCH demodulation performance cannot be met.